I voted for make the game more complex and add further complexity later on.
Settler difficulty is for beginners. IMHO I've enjoyed civ5 so much because I was a semi-casual civ4 gamer who rarely ventured into emperor territory, much less immortal+.
Don't get me wrong, you know I'm a huge fan of civ5, but...
Sid has really turned off a huge part of his fanbase imho with the current game. And the part that he turned off is generally the most dedicated fans, the true civ lifers, the ones who sang civ4's praise to the high heavens once bts turned it into such a gem. A better way to bilk more money out of users would have been to find a way to make it MMO-like with monthly subsription fees. The 1% diehards would have paid the money for it instead of trashing the game if it was truly an improvement on bts.
Of course, many many users have issues not with the core of the game itself but rather the horrible unfinished state in which it shipped. The blame for that goes to firaxis/EA. Maybe if they hadn't laid off 1/2 the company right before launch they would have gotten enormous positive buzz instead of the hate feedback that they got instead.